Apple forcing developers to ditch unique device IDs

As of May 1, Apple's also cracking down on apps that don't support iPhone 5.

Data like location, Facebook profile, and other information could be correlated from multiple databases to piece together an individual's identity using the UDID.

Apple will officially start rejecting iOS apps that make use of the unique device ID or UDID, in order to track users. The company informed its developer community of the policy late Thursday (followed by a confirmation to Macworld) that it would no longer accept UDID-utilizing apps as of May 1. Instead, the company instructed developers to make use of other identifiers, such as Apple's new Identifier for Advertising, or IDFA, which was introduced in iOS 6 last fall.

That's part of why Apple introduced its IDFA when it rolled out iOS 6. Not only do users have more control over whether they are being tracked; the IDFA also allows developers to follow iOS users across devices. With the UDID, users had no way to turn off the ad tracking, and since the UDID was tied to a specific device, the data could be cross-contaminated if a new user took control of it.

The no-UDID policy isn't the only thing Apple announced this week. The company also told developers that as of May 1, it will no longer accept apps that have not been adapted to the iPhone 5's taller 4-inch screen, or those that don't support retina displays.